MIDLAND CITY, Ala. - Police, SWAT teams and FBI negotiators kept vigil Wednesday near an underground bunker in rural Alabama where a gunman was holding hostage a 6-year-old boy he had snatched from a school bus Tuesday after killing the driver, authorities and neighbors said.

A law enforcement official who is not authorized to speak to the media identified the man as 65-year-old Jimmy Lee Dykes, a retired truck driver and Navy veteran. Neighbors said he was scheduled to appear in court Wednesday for pointing a gun at residents last month in a dispute over a speed bump.

He reportedly is connected to the anti-government survivalist movement.

Patricia Smith, who lives across the street from Dykes in this rural community in far southeastern Alabama, said her children had been on the bus about 3:30 p.m. Tuesday when the shooting occurred.

They told her that two other children had just been dropped off when Dykes stepped onto the bus and grabbed the door so that the driver couldn't close it.

Dykes told the 66-year-old driver, Charles Albert Poland Jr., that he wanted two boys, 6 to 8 years old, without saying why, Smith said. The suspect tried to step into the aisle of the bus, but Poland put his arm out to block him. Dykes fired four shots at Poland with a handgun, Smith said.

The suspect then took the boy to a homemade bunker that he had apparently been constructing for years on his nearby property.

Poland, who had been a school bus driver since 2009, died later.

Authorities said Dykes lives in a small trailer at the end of a red dirt road, but they gave few details about the hostage standoff or whether Dykes had made any demands.

State Rep. Steve Clouse, who met with authorities and visited the boy's family, said that the bunker had food and electricity, and that the boy was watching TV.

The unidentified boy was among 21 students on the bus driven by Poland, who was well known and highly regarded in the string of small towns that make up Dale County.

"He was a good guy and he loved to help people," said Terry Howard, the interim pastor at First Assembly of God in Newton, Ala. "He was a likable fellow. He would help people all the time, help the elderly ladies fix their air conditions or help cut the grass."

Howard chatted with Poland a month ago.

"We were talking about the bus. He talked about how he really loved being with the kids," Howard said.

Protecting the children "would be in his nature," he added, noting that Poland's wife is a substitute teacher.

Authorities communicated with the suspect through a PVC pipe connected to the bunker, WSFA-TV reported, and were also able to pass some unidentified medicine for the boy.

Neighbors said Dykes had lived for about a year at the residence in Midland City, population 2,300. Before that he spent time in Texas and in Panama City, Fla., The Dothan Eagle reported.

Florida Department of Law Enforcement records show he was arrested in Panama City in February 1995 and charged with improper exhibition of dangerous weapons or firearms, a misdemeanor. The charge was dismissed four months later.

The Southern Poverty Law Center's Hatewatch, which tracks radical hate groups, said Tim Byrd, chief investigator with the Dale County Sheriff's Office, described Dykes as having "anti-America" views and ties with the antigovernment "survivalist" movement.

"His friends and his neighbors stated that he did not trust the government, that he was a Vietnam vet, and that he had PTSD," Byrd said, according to Hatewatch. "He was standoffish, didn't socialize or have any contact with anybody. He was a survivalist type."

Michael Creel, who lives nearby, told The Dothan Eagle that Dykes' bunker, similar to those used against tornadoes, was four feet wide, six feet long and about eight feet deep, covered in sand.

Neighbor Mike Smith said Dykes once threatened to shoot his children when the family's dogs entered his property.

Dale County Sheriff's deputies arrested Dykes on Dec. 22 and charged him with menacing for a Dec. 10 complaint, court records show. He spent four days in jail before posting the $500 bail. His trial was to have begun Wednesday at 9 a.m.

Neighbor Ronda Wilbur said Dykes was known to go out in the middle of the night to shoot birds and rabbits. She said Dykes had cut down nearly all the trees on his lot, erected a wire fence and "would go berserk" if a dog strayed onto his land.

Other neighbors said he had beaten a dog to death with a lead pipe.

Nearby residents were evacuated from their homes as a precautionary measure, said Rachel David, a spokeswoman for the police department in the nearby town of Dothan.

The Dale County, Daleville City and Ozark City school systems canceled classes on Wednesday because of the standoff.